N250 Medication Calculation Practice Exam (with Key)

Hours to AdministerHow many hours are required to administer the following fluids at the given rates?

1. Rate: TPN 1000 ml at 30 ml/hrHours?

ANS: or 3 hours 20 minutes

2. Rate: D5 NS 1000 ml at 125 ml/hrHours?

ANS:

Drop RateCalculate the drop rates (drops per minute; gtt/min) for the following:

3. D5 NS at 125 ml/hra. 10 gtt/ml?b. 15 gtt/ml?c. 20 gtt/ml?d. 60 gtt/ml?

ANS:a.

(remember drops must be in whole numbers)b. 31 gtt/minc. 42 gtt/mind. 125 gtt/min

4. D5 NS at 75 ml/hra. 10 gtt/ml?b. 15 gtt/ml?c. 20 gtt/ml?d. 60 gtt/ml?

ANS:

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IV Mini Bag

a. or 13 gtts/min (no partial drops)

b. 19 gtt/minc. 25 gtt/mind. 75 gtt/min

Antibiotics—IntravenouslyAnswer these questions: a. What is the correct drug dose?b. What is the drop rate in gtt/min?

5. Give amikacin 800 mg IVPB, nowAvailable: Amikacin 500 mg/2 mlSet and solution: D5W 150 ml minibag and a drop factor of 15 gtt/ml setInstructions: Infuse over 60 mina. Drug dose?b. Drop rate?

ANS:a.

b.or 38 gtts/min

6. Give nafcillin 250 mg IVPB q4hAvailable: Nafcillin 500 mg and 1.8 ml diluent to yield 2 mlSet and solution: Buretrol with a 60 gtt/ml drop factor and NS (normal saline) 500 mlInstructions: Dilute in 50 ml and infuse over 30 min

a. Drug dose?b. Drop rate?

ANS:a. 1 ml (500mg/2ml = 250mg/1ml)b. 51ml X 60gtt/ml = 102 gtt/min

30 min

7. Give tobramycin (Nebcin) 60 mg IVPB q6hAvailable: See label belowSet and solution: 50 ml bag D5W and a set with a 15 gtt/ml drop factorInstructions: Dilute with 50 ml and infuse over 30 min

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Buretrol

D5W 500ml

Where you find the drop factor on the IV tubing package

a. Drug dose?b. Drop rate?

ANS:a. 1.5 ml (80mg/2ml = 40mg/1ml; 60mg = 1.5 ml)b. 51.5 ml X 15 gtt/ml = 25.75 gtt/min = 26gtt/min

30 min

8. Give cephradine 1 g IVPB q6hAvailable: Cephradine 500 mg, add 4.5 ml diluent to each vial to yield 5 ml/vialSet and solution: 50 ml bag of D5W and a set with a 15 gtt/ml drip factorInstructions: Infuse over 30 min

a. Drug dose?b. Drop rate?

ANS:a. 10 ml (500mg/5ml = 100mg/ml; 1000mg = 10ml)b. 60ml X 15gtt/ml = 30 gtt/min

30 min

9. Give oxacillin 250 mg IV q4hAvailable: See label below

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Set and solution: 100 ml bag of D5W and a set with a 20 gtt/ml drop factorInstructions: Infuse over 1 houra. Drug dose?b. Drop rate?

ANS:a. 1.5 ml (250mg/1.5ml)b. 101.5 ml X 20gtt/ml = 33.8333 gtt/min = 34 gtt/min

60 min

10. Order: Heparin units 8000, subQ, q6hDrugs available:

a. Which heparin would you use?b. How many milliliters of heparin would you give per dose?

ANS:a. Heparin 10,000 unitb. 0.8 ml of heparin per dose

11. Order: Enoxaparin (Lovenox) 30 mg, SQ, bid, post-hip surgeryDrug available:

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a. The patient should receive Lovenox how many times a day?b. How many milliliters (ml) should the patient receive per dose?

ANS:a. 2 times a dayb. 0.3 ml per dose of Lovenox

12. Order: Vitamin B12 500 mcg, IM, 2 per weekDrugs available:

a. Which cyanocobalamin cartridge would you use?b. How many milliliters of cyanocobalamin would you give?

ANS:a. Cyanocobalamin 1000 mcg/mlb. 0.5 ml of the drug

13. Order: Kanamycin (Kantrex) 400 mg, IM, q8hPatient weight: 90 kgDose parameter: 15 mg/kg/day in two or three divided dosesDrug available:

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a. What is the dose parameter according to the patient’s weight?b. How many milligrams would the patient receive per day?c. Is the drug dose within safe dose parameters?d. How many milliliters of Kantrex would you give per dose?

ANS:a. 15 mg 90 kg = 1350 mgb. 1200 mg of Kantrex per dayc. Yes, dose per day (1200 mg) is less than maximum dose (1350 mg).d. 1 g = 1000 mg; thus,

OR

DA:

14. Order: Diazepam (Valium) 10 mg, IM, statDrug available:

a. How many milliliters (ml) should the patient receive?

ANS:a. 2 ml of diazepam

15. Order: Prochlorperazine (Compazine) 7.5 mg, deep IM, statDrug available:

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a. How many milliliters of Compazine would the patient receive?

ANS:a. 1.5 ml of Compazine deep IM stat

16. Order: Cefazolin (Ancef) 0.25 g, IM, q6hDrug available:

a. How many milliliters of diluent would you add?b. After reconstitution, how many milliliters of cefazolin solution would you have?c. How many milliliters of Ancef would you administer per dose?

ANS:a. 2 ml of diluentb. 2.2 ml (= 500 mg)c. 0.25 g = 250 mg; thus, give 1.1 ml of Ancef per dose

17. Order: Ethambutol HCl 800 mg, PO, qidParameter: 15 mg/kg/dayPatient weighs 121 lbDrugs available: Ethambutol 100 mg and 400 mga. How many kilograms does the patient weigh?b. What is the maximum dose the patient should receive per day?c. Which bottle of ethambutol would you use?d. How many tablet(s) would you give?

ANS:a. 121 lb ÷ 2.2 kg = 55 kgb. 15 mg 55 kg = 825 mg/day; dose is within safe dose parameter of 825

mg/day.c. Ethambutol 400 mg bottled. 2 tablets from ethambutol 400 mg bottle per day

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18. Order: Timolol maleate (Blocadren) 10 mg, PO, bid; then, after 2 weeks, the patient is to receive 40 mg in two divided dosesDrug available:

a. Which bottle of Blocadren would you choose for the first 2 weeks?b. How many tablet(s) should the patient receive per dose during the first 2 weeks?c. Which bottle of Blocadren would you choose after the first 2 weeks? Why?d. How many tablet(s) should the patient receive per dose after the second week?

ANS:a. Blocadren 10 mgb. 1 tablet of Blocadren of 10 mgc. Blocadren 20 mg; fewer tablets to gived. 1 tablet of Blocadren of 20 mg

19. Order: Phenytoin (Dilantin) 1 g, PO, loading dose (LD) in three divided doses in 24 hrParameter: 15 to 18 mg/kg/LDPatient weighs 60 kgDrug available: Dilantin 100 mg capsulea. In 24 hr, three divided doses would be every _____.b. How many milligrams would the patient receive per dose in 24 hr?c. Is the dose within safe parameters? Explain.d. How many capsule(s) would you give per dose?

ANS:a. 8 hours (q8h)b. Per dose: (1) 300 mg, (2) 300 mg, and (3) 400 mgc. Yes, the dose is within safe dose parameters (900–1080 mg). Parameters: 15 mg

60 = 900 mg; 18 mg 60 = 1080 mg8

d. (1) 3 capsules, (2) 3 capsules, and (3) 4 capsules

20. Order: Doxycycline monohydrate (Vibramycin) 100 mg, PO, initially; then 100 mg, PO, in two divided doses per dayDrug available:

a. How many milliliters (ml) should the patient receive initially?b. How many milligrams (mg) should the patient receive per dose after the initial

dose?c. How many milliliters (ml) should the patient receive per dose after the initial

dose?

ANS:a. 20 ml initiallyb. 50 mgc. 10 ml

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